Sheet reading and sorting machines for sorting such as postal items read the postal code and the address indicated on deliveries as the sorting destination with a scanner, and recognize the read image data by OCR (with a recognition unit), for example. The sheet reading and sorting machines perform a sorting process of sorting to the sorting destinations based on the result of this recognition. These sheet reading and sorting machines include a sheet take-out device for taking out sheets.
The take-out performance of this sheet take-out device depends largely on the size, in the conveying direction, of the handled sheets. There is a problem in that if sheets whose length in the conveying direction is short are handled, the conveying pitch is long relative to the sheets, so that the processing efficiency is reduced accordingly. In order to solve this problem, a method is known in which when sheets have the same length in the conveying direction, that length in the conveying direction is measured, and the take-out speed is changed according to the length of the sheets so as to adjust the gap between the sheets, thereby improving the sheet processing efficiency (e.g., see Patent Document 1).
Also, there is a problem in that errors such as overlapped feeding, a failure in taking out sheets, and the like occur if sheets are supplied to a take-out unit in a tight state. In order to solve this problem, in conventional techniques, the floor belt on which sheets are placed is rotated in reverse for a predetermined period of time, such that the sheets are separated away from the take-out unit in a poor take-out state so as to be put in a loose state.